The interaction of copper with human serum albumin is being examined with the aid of a number of spectroscopic techniques. In addition to albumin itself, binding studies are also beimg made with the N-terminal tripeptide of albumin and with larger peptide fragments isolated from enzymatic digestion of albumin. In these studies the amino acids that function as chelation sites for copper will be identified. This work will provide a molecular basis for the interaction between copper and human serum albumin in both normal and diseased states (Wilson's disease, rheumatoid arthritis and Bechterew's disease).